refactor(view) Delete redundant SPAN element.

"span" container for list item content was deleted. "class" and "id" attributes moved to parent LI element.
feature(initialization) Support for initial UL element

If "container" element (constructor first argument) contains UL element, it items (LI elements with nested UL elements) will be used as initial data in addition to "nodes" (constructor second argument).
fix(sorting) Support for user defined items order

Tree items sorted in order specified by the user through the order of calling the addItem() method.
fix(findItem) Fixed TreeNode.findItem()

Fixed recursive invoking on TreeNode items.
chore(js) Update compiled files.